JEFFERSON COUNTY, Colo. (CBS4) – Trails at the new Rocky Flats National Wildlife Refuge officially open to the public this weekend in Jefferson County.

CBS4 reported last week, one trail head is already open.

READ MORE: Mountain Lions Thwart Planned Relocation Of Bighorn Sheep


The superfund site has been off limits for years. It was once a government facility to build parts for nuclear weapons during the Cold War.

READ MORE: Kaiser Permanente Sets Out To Add Thousands More To Vaccinated List


Environmentalists sued to stop the trails from opening, saying they are unsafe.

MORE NEWS: Explosion & Fire At Elkins Distilling In Estes Park Hospitalizes 2 People

Officials say the land is clean and safe for hikers and bikers to enjoy.